Summary about Disease
Pneumonic plague is a severe lung infection caused by the bacterium Yersinia pestis. It's one of three main forms of plague (bubonic, septicemic, and pneumonic). Pneumonic plague is the most virulent and least common form, and it's the only form that can spread directly from person to person via respiratory droplets. Untreated, pneumonic plague progresses rapidly and can be fatal within 24-48 hours.
Symptoms
Symptoms of pneumonic plague usually appear abruptly, after an incubation period of 1-3 days. Common symptoms include:
Fever
Cough (often with bloody or watery sputum)
Chest pain
Difficulty breathing (shortness of breath)
Rapidly developing pneumonia
Headache
Weakness
Bloody or watery sputum
Nausea
Vomiting
Causes
Pneumonic plague is caused by the bacterium Yersinia pestis. It can occur in two ways:
Primary Pneumonic Plague: Inhaling infectious droplets released into the air by a person or animal (usually a cat) with pneumonic plague.
Secondary Pneumonic Plague: When Yersinia pestis bacteria spread to the lungs from another part of the body (e.g., from bubonic plague or septicemic plague).
Medicine Used
Prompt antibiotic treatment is crucial for pneumonic plague. Effective antibiotics include:
Streptomycin
Gentamicin
Doxycycline
Ciprofloxacin
Levofloxacin
Chloramphenicol Treatment should begin as soon as pneumonic plague is suspected, ideally within 24 hours of symptom onset.
Is Communicable
Yes, pneumonic plague is highly communicable. It is the only form of plague that can be spread directly from person to person through respiratory droplets produced when an infected person coughs, sneezes, or speaks.
Precautions
Avoid contact: Avoid close contact with people who have pneumonic plague.
Wear a mask: Healthcare workers and others in close contact with infected individuals should wear appropriate personal protective equipment, including respirators (N95 or higher).
Isolation: Isolate infected individuals to prevent further spread.
Prophylactic antibiotics: People who have been in close contact with someone with pneumonic plague should receive prophylactic antibiotics to prevent infection.
Rodent control: Control rodent populations in areas where plague is endemic.
Vaccination: There is no plague vaccine currently available in the United States.
How long does an outbreak last?
The duration of a pneumonic plague outbreak depends on several factors, including the speed of detection, the effectiveness of control measures (antibiotic treatment and prophylaxis), and the overall public health response. An outbreak can be contained relatively quickly (within weeks) with rapid diagnosis and treatment. However, if detection is delayed or control measures are inadequate, the outbreak could last longer (months).
How is it diagnosed?
Diagnosis of pneumonic plague involves:
Clinical suspicion: Based on symptoms (fever, cough, chest pain, rapid pneumonia) and potential exposure.
Laboratory tests:
Sputum culture: To identify Yersinia pestis in the sputum.
Blood culture: To detect Yersinia pestis in the blood.
Gram stain: Examination of sputum under a microscope.
Serological tests: To detect antibodies to Yersinia pestis in the blood (may not be helpful early in the disease).
PCR (Polymerase Chain Reaction): To detect Yersinia pestis DNA in sputum or other samples.
Chest X-ray: Shows signs of pneumonia.
Timeline of Symptoms
Incubation period: 1-3 days (time between exposure and the start of symptoms)
Day 1-2: Abrupt onset of fever, headache, weakness, cough.
Day 2-4: Rapidly developing pneumonia, chest pain, bloody or watery sputum, difficulty breathing.
Day 3-5 (Untreated): Respiratory failure, shock, and death.
Important Considerations
Pneumonic plague is a medical emergency.
Early diagnosis and prompt treatment with antibiotics are crucial for survival.
Public health authorities should be notified immediately of suspected cases to implement control measures and prevent further spread.
Healthcare workers must take appropriate precautions to protect themselves from infection.
Mortality is near 100% if left untreated.